As for the martyrdom of Christians it has to be remembered that history is
often written by the victors and that the persecution of
Christians was limited to a number of particular periods and circumstances.
Clearly this doesn't mean that atrociously gory persecutions and martyrdoms
didn't happen, they did, but in the midst of a huge number of other gory
executions. The Jews were also persecuted for example, in fact for a long time
the Christians were simply regarded as a Jewish sect.

We simply have to consider some of the antics displayed in the Colosseum to
imagine the variety of attractions which were dreamt up to keep the plebs
distracted whilst at the same time minimising anti Imperial sentiments amongst
the wider population.

Although historically Christian martyrdom has been closely associated with the
Amphitheatre the execution of Christians was more likely to be held in the
Circus of chariot races . It was usual for the executions to take on other forms
such as crucifixion, for example rather than Gladiatorial fight or "damnatio
ad bestia" (thrown to the wild beasts).

The Catholic church of the
Middle Ages and Renaissance maintained and
strengthened this view of the Colosseum. Various crosses in the
middle of the arena and the twelve stages of the Crucifixion were regularly used
for religious displays and processions. The Colosseum became closely associated
with Christian martyrdom, providing a useful counterpoise and memorial to the Christian religion's belief
in life.

The first Christian martyred in the Coliseum is
said to have been St Ignatius who was thrown to the lions and (aparently)
exclaimed "I am as the grain of the field and must be ground by the
teeth of the lions, that I may become fit for His table."

Although some Christians certainly died in the Colosseum there seems to be
little reference to the supposed rivers of (Christian) blood which were supposed to
have flowed out of that building in particular during Domitian's notorious
"Second Persecution".

Nevertheless we do know that 115 Christians were executed with arrows,
shortly after Ignatius. At the beginning of the third century a family of
Christians, who also happened to be Roman Patricians,
were reputedly roasted (in a bull) and that four Christians called Sempronius,
Olympius, Theodolus and Exuperia were burned alive in front of Nero's colossal
statue, which had been stood by the Colosseum: Jews and Christians were often
given a last chance of respite by paying their respects to the
Emperor-Divinity's image, which of course monotheism doesn't allow.

This refusal to join in any of the state's religious practices was the really
irreconcilable problem: on one occasion during the reign of the benevolent
Emperor Marcus
Aurelius the Christians gave rise to a new wave of hate against them as they
refused to participate in the religious rites aimed at checking an epidemic of
plague which was decimating the population. The Emperor had little choice but to
persecute thousands of them to a hideous death in the Amphitheatre and for as
much as he hated the gladiator shows he
attended out of a sense of duty.

As for Nero's
persecution of the Christians, this could not have had any episodes in the
Colosseum, given that the Flavian Amphitheatre as it was then known, was not yet
constructed. This of course doesn't mean that Nero didn't persecute the
Christians: he did. Quite awful things too, like dousing them with oil and
setting them alight for example or dressing them up in animal skins and setting
dogs onto them.

All this sounds like an excuse for the various Christian persecutions which
certainly did happen and often they were quite forceful and brutal, especially
since the Christians were increasingly viewed as subversive traitors by both the
authorities and the non Christian population. Truth of the matter is they were
subversive traitors who were trying to change the system and, true to its
nature, the system reacted against them in a brutal way.